Fork help

6 replies to this topic
  • Hoody UK

Posted September 17, 2014 - 03:32 PM




I have a WR450F 2007 with an alloy frame. I use it for Enduro racing in the UK. The front forks have leaked a few times, but with a clean up they do not leak. I decided to take the forks out, unscrew the caps, slide the outer part all the way down and drain the oil out. I then refilled the outer tubes with fresh oil about one and a half inches from the top of the outer tube, slid the outer tube back up and screwed back together. I used 550ml of oil in each fork.

Can someone advise if I have done wrong or right please.



  • stevethe

Posted September 17, 2014 - 03:49 PM


Your off on your oil level. It's suppose to be 95mm to 150mm from the top without the spring. That's collapsed. If you pulled the forks out too far your seals may leak. Sounds like you should download a shop manual.
You should also see that your base valves have all shims instead of the stock little spring and two shims.

  • Hoody UK

Posted September 17, 2014 - 04:13 PM


I cleaned the seals with a seal mate, I have not taken the shocks apart. I just unscrewed the cap, slid the outer down, empty the oil and poured new in with everything in place including the spring. I read somewhere you could do this, but I am unsure of the level, I also know it is not the correct way but I thought some oil in there is better than none?

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  • RMK800

Posted September 17, 2014 - 04:36 PM


Your way off on your oil level. That would be a very firm ride. You need to measure 5.2 inches down with fork fully compressed without spring. You can try to stick a measuring device down 5.2 or get a Tusk measuring tool that will suck the oil out to the specified inches.


ImageUploadedByThumper Talk1411000545.553085.jpg

Get a service manual.

Here is a great video on changing seals and oils on single chamber KYB forks. This is the first of a two part video. The second video shows how to set the oil level.

Edited by RMK800, September 17, 2014 - 04:41 PM.

  • Hoody UK

Posted September 17, 2014 - 05:17 PM


Thank you for the information, the video is great for me. I know what I will be doing tomorrow after work? Doing it again correctly :facepalm:

  • RMK800

Posted September 17, 2014 - 05:29 PM


Your welcome. I've lived in the UK for a few years. Nice place. Here is the link to the second part video.

Edited by RMK800, September 17, 2014 - 05:37 PM.

  • Hoody UK

Posted September 18, 2014 - 12:46 PM


@ RMK800; I had already found part two, I have just finished and set both to 132mm from the top without the spring, basically followed the video without changing the seals and bushings, I will do that over the winter as it will be my excuse not to ride in our extreme conditions :-)

Thank you once again for the great advise and links, appreciated :thumbsup:


@stevethe; When I rebuild the forks fully over the winter I will look into what you are saying about the base valves. Thanks.


............ Hoody


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